In many applications, after the use of chairs, the chairs must be overlapped for storage. Thus there are some designs of chairs which are aimed at to make a compact structure of chair so that the chairs can be overlapped firmly and safely.
One prior art, Taiwan Patent No. 160984, the end of chair leg is installed with a protruded pad which is buckled with a resisting end at an upper end of a leg of another chair so as to have a firm structure in overlapping. However, the pad will wear as it contacts the ground for a long time period. Finally, the pad will lose of function for resisting with the resisting end. As a result, the overlapping of the chairs are not firmly and steadily and the chairs easily fall down. Furthermore the pads and resisting ends only serve to prevent the chairs from falling down forwards or backwards, but it can not prevent the chairs from falling down leftwards, or rightwards. Thus, when the chairs are overlapped to a predetermined height, the stacks of the chairs easily fall down leftwards or rightwards so as to hurt people asides or destroy the chairs.
Besides, one end of the seat frame of the handle is locked a back of the chair and another end thereof is a concave supporting portion. The supporting portion is buckled to an upper side of a chair leg at a rear side. Then a half combined clamping portion is combined to a lower side of the leg. Then a pair of screw units are locked to the leg at the rear side. However, many components are used and thus the structure is complicated and the more part makes more cost.